The Metallurgy of the Common Metals, Gold, Silver, Iron, Copper, Lead, and Zinc. Leonard S. Austin

1910 The Journal of geology  
REVIEWS following propositions concerning the propagation of the seismic energy of the earthquake: i. The propagation is most rapid in the direction of the strike of the rock layers, and slowest perpendicular thereto. 2. Breaks (Briiche) in the earth's shell oppose to the propagation a very considerable obstacle. It appears that the great rift of the fossa magna, first made known by Naumann, has played an important r81e in the seismic history of Japan. F. OMORI. "Report of the Observation of
more » ... e Observation of Pulsatory Oscillations in Japan" (ist paper), Bull. Imp. Earthq. Invest. Comm., Vol. III, No. I, 1909, pp. 1-35; pls. 1-6. This study, though carried out in Japan, was made in consequence of the resolution adopted at the I907 conference of the International Seismological Association, and had for its object the observation of pulsatory movements on isolated islands and the comparison of the motions observed at several stations within a small area. Dr. Omori has found that these pulsatory motions of seismographs, as regards their periods of vibration, are practically the same all over the earth, and that they are probably due to the translatory movements and not to the inclination of the ground. There are found to be two mean periods of vibration: a short one, Q =4.4 seconds, and a longer one, Q,=8.o seconds. The movements occur very frequently, in fact almost constantly, on broad alluvial plains, though but rarely in places situated on granite or Paleozoic rocks. Though up to the present, they have generally been registered on instruments which record horizontal components only, they are found to have a vertical component as well. Marked pulsatory oscillations are connected with the approach of an area of low barometer, these movements being especially those of the shorter period. In the second edition of this work much of the material has been recast and numerous text figures have been added, with about 100 pages of descriptive matter. This edition contains a comprehensive index, the lack of which was a serious omission to the first edition. The description of the cyanide process has been greatly amplified and much data relating to recent improvements in the practice are included. The metallurgy of zinc, the
doi:10.1086/621713 fatcat:a6fbhuufhnb2vhlrbvt5ipg5b4